The recent interest in contemporary architecture, particularly in connection with residential building, has resulted in a very substantial increase in the demand for skylight assemblies, either fixed glazing type or of the operating (openable) type. In either case, ease of manufacture (with resultant lowered cost) and ease of installation are important objectives in designing the skylight assemblies. Since these skylight assemblies are installed in structures having a wide range of pitches (from almost flat roofs to mansard walls which are almost vertical), two additional important criteria must be met in the design of such assemblies. First, extreme care must be taken to insure that the assembly provides a leak-free interface with the structure in which it is to be mounted. Secondly, and this requirement is also related in part to the first, it is preferable that the assembly be fastened to the structure from the interior of the structure in a manner which is both aesthetically acceptable and, at the same time, does not affect the watertight integrity of the overall condition of roof and skylight.
Typically, in prior skylight assemblies, separate flashing materials (e.g. copper or aluminum or plastic sheets) are attached at the junction of the skylight assembly and the roof in the same manner as is employed, for example, with chimneys or other vertical structures. That type of configuration usually entails inserting nails, screws or other penetrating fasteners through the flashing material into the roof sheathing and thereafter sealing the resulting holes with roof cement. Other arrangements have been proposed utilizing an extruded plastic flashing flange integral with or fastened to one or another type of curb assembly (see, for example, U.S. Pat. Nos. 4,449,340; 4,455,799; 4,527,368; 4,570,394; 4,466,221 and 4,589,238 for typical alternative arrangements). Furthermore, in such prior arrangements, the skylight assembly itself is often fastened to the roof structure by nailing or inserting other penetrating fasteners from the outside through both the skylight materials and the roof. Thereafter, cement is applied to attempt to achieve a watertight assembly. Such configurations are subject to leaking and may have a relatively limited leak free lifetime.
These and other problems related to prior practices are intended to be overcome by the present invention.